Partial Lunar Eclipse of June 26

The first lunar eclipse of 2010 occurs at the Moon's ascending node in western Sagittarius about 3° east of the Lagoon Nebula (M8). It is visible from much of the Americas, the Pacific and eastern Asia (Figure 2). The Moon's contact times with Earth's shadows are listed below.

Partial Eclipse Begins: 10:16:57 UT
Greatest Eclipse: 11:38:27 UT
Partial Eclipse Ends: 12:59:50 UT
Penumbral Eclipse Ends: 14:19:34

At the instant of greatest eclipse4 the umbral eclipse magnitude5 will reach 0.5368. At that time the Moon will be at the zenith for observers in the South Pacific. In spite of the fact that barely half of the Moon enters the umbral shadow (the Moon's northern limb dips 16.2 arc-minutes into the umbra), the partial phase still lasts 2 2/3 hours.

Figure 2 shows the path of the Moon through the penumbra and umbra as well as a map of Earth showing the regions of eclipse visibility. New England and eastern Canada will miss the entire eclipse since the event begins after moonset from those regions. Observers in western Canada and the USA will have the best views with moonset occurring sometime after mid-eclipse. To catch the entire event, one must be located in the Pacific or eastern Australia.

Table 3 lists predicted umbral immersion and emersion times for 15 well-defined lunar craters. The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see Crater Timings During Lunar Eclipses).

The June 26 partial lunar eclipse belongs to Saros 120, a series of 83 eclipses in the following sequence: 21 penumbral, 7 partial, 25 total, 7 partial, and 23 penumbral lunar eclipses (Espenak and Meeus, 2009). Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/LEsaros/LEsaros120.html